Hi Poorvi,
Business promotion expenditure are not specifically covered in the "input services".
However, you don't need to be dissapointed because of that. Main part of "Input Services" definition is the services (in your case hotel services) must be used by you for providing the output services (in your case interior decorator services).
If you can prove to the department that the business promotion expenditure actually used for providing interior decorator services then certainly you can take CENVAT Credit against the same. However, you must be ready to pool your sleves up to proove it by providing appropriate and adequent documents (e.g. invoice, payment granted by you etc.). Additionally, you also have to prove that the hotel services are not used for personal or your staff consumption as any service consumed personally or by staff; CENVAT Credit of the same can not be availed and utilised.
Hope you got your answer.
Warm Regards.